Helping cross-laminated timber go mainstream

ESSB 5450 directs the Washington State Building Code Council to adopt rules for cross-laminated timber (CLT) and other similar wood products. It’s a move that has been advocated by conservationists and forest health experts to restore the state’s mill infrastructure while removing small-diameter trees that make state forestland susceptible to severe wildfires. Photo:

Cross-laminated timber (CLT) isn’t a silver bullet for Washington’s rural economy and public forestland health, but it may be as close as it gets.

The result of gluing several layers of lumber to form a single wood panel, CLT offers the promise of efficient construction for developments, a revitalized mill infrastructure for struggling rural economies and improved forest health by removing small-diameter trees that are susceptible to overcrowding and ill-suited for other uses.

However, obstacles for increased use of CLT include a building code not yet updated to reflect technological advances, as well as the need for state officials that issue necessary permits to become more aware of and familiar with the product. The state Senate took a large step to address these issues by overwhelmingly approving a bipartisan bill that directs the Washington State Building Code Council (WSBCC) to adopt rules for CLT use when building residential and commercial buildings.

“I think this bill is really a big step for the economy and for Washington state,” Sen. Tim Sheldon (D-35) said on the Senate floor prior to the February 12 vote. “We have a state which has grown up because of wood products, because of the big mills that we had and the jobs that they provided. The opportunities for cross laminated timber I think are endless. These new rules…will make it possible for Washington to be a leader in this industry.”

The prime sponsor of ESSB 5450 is Majority Floor Leader Marko Liias (D-21), who introduced the bill during last year’s session. It remained held up in the Senate Local Government Committee after two public hearings and was eventually given a “do pass” recommendation after it was reintroduced this year.

Liias told colleagues that CLT could encourage more development, and job growth, in rural communities. “In Scandinavia, they use these mass timber products extensively. In some of the Scandinavian countries they have 20-30 story tall wood buildings, something that was unheard of a few decades ago. But the advances in engineering and technology have led to this.”

He added: “To me when I heard…an idea that comes from Scandinavia that could have real positive impacts in some of the most struggling rural communities in my county and across the state, it seemed like a win-win.”

Senator Shelly Short (R-7) agreed. “We have such an incredible state, such incredible, diverse products; and this I am confident will be one of those in the future for building products.”

An amendment proposed by Sen. Dean Takko (D-19) and adopted by the Senate has the WSBCC also add rules for seven other wood products similar to CLT such as glue-laminated timber.

CLT is a relatively new industry, with the first Washington-based CLT mill facility in the eastern part of the state recently opened by Vaagen Bros.

It has been cited by conservationists and forestry experts alike as a way to improve the health of state forestland while decreasing the costs for those projects. One region in particular that requires restoration work is the Olympic Peninsula, where timber harvesting ceased in the early 1990s. Replacing the old growth trees that have been harvested are densely-packed, small-diameter trees unsuitable for normal wood products. Those trees can be removed through precommercial thinning projects but can prove costly because the leftover material has little to no market sale value.

“What’s happening is the timber’s been growing since the 1990s and the cutting has stopped,” Sheldon said. “That small timber…is perfect for this type of technology.”

The state Department of Natural Resources made a similar conclusion as part of its 20-year forest health plan as a way to minimize project costs. Also promising for CLT supporters were the results of a 2016 study by Forterra, the state’s largest land conservation, stewardship and community building organization. It concluded that despite its current limited use, “growing interest in CLT and anticipated, expanded allowances for CLT-based construction … suggest a market will emerge.”

If approved by the House and signed by Governor Jay Inslee, the law will be well-timed with the annual Mass Timber Conference in Portland, Oregon scheduled for March 20–22. One of the keynote speakers is Katerra Chairman and Founder Michael Marks, whose technology company is building a new mass timber factory in Spokane Valley to manufacture CLT, among other products. To test its CLT, the company has partnered with the Washington State University Composite Materials and Engineering Center.

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